a) `-2/3:x+5/8=-7/12`
`⇒-2/3:x=-7/12-5/8=-29/24`
`⇒x=(-2)/3: (-29)/24=2/3. 24/29=16/29`
Vậy `x=16/29`
b) `(2x+3)^2=25=(±5)^2`
\(⇒\left[ \begin{array}{l}2x+3=5\\2x+3=-5\end{array} \right.\)
\(⇒\left[ \begin{array}{l}2x=2\\2x=-8\end{array} \right.\)
\(⇒\left[ \begin{array}{l}x=1\\x=-4\end{array} \right.\)
Vậy `x=1; -4`